Twisting apparatus



Oct. 25, 1960 FIG.|

W. LENK EI'AL TWISTING APPARATUS Filed July 2, 1959 INVENTORS: WALTER LENK HANS LOHEST ATTV'Y S United States Patent TWISTING APPARATUS Waiter Lenk and Hans Loirest, Remscheld-Lennep, Germany, assignors to Banner Maschinenfahrik Aktiengeseilschaft, Remscheid-Lcnnep, Germany Filed July 2, 1959, Ser. No. 824,685

Claims priority, application Germany July 5, 1958 4 Claims. (Cl. 57-77.3)

The invention, in general, relates to the plying or twisting of two or more filamentary elements such as yarns, threads and the like in a pseudo-twist and the winding of these pseudo-twisted threads, yarns, etc., and more particularly, to improvements in machines for said plying and winding.

The plying of the threads, yarns, filaments, etc., hereinafter referred to as yarns, is done in accordance with the general principles of US. Patent 2,882,674, issued on April 21, 1959, to Walter Lenk, by a procedure wherein the individual yarns, drawn from separate feed points, directly or during their take-up onto the take-up bobbin receive an alternating twist and are wound with this alternating or pseudo-twist. The purpose of providing a plurality of alternating twists in each superposed yarn layer on the winding bobbin or spool is to give individual yarns having the threads so far as possible, the same length and preliminary tension. In the latter unwinding from the bobbin or spool, the yarns can be drawn otf in the form of a group of endless, parallel individual yarns under uniform tension for further processing or fabricating into textiles.

In further development of the practice of the invention described in said patent, we propose, in accordance with our present invention, to use as the alternatingtwister a reversing motor, in particular a single-phase, condenser motor constructed according to the Ferraris principle, the well known Ferraris motor. This motor has an axially drilled shaft and means for guiding and imparting the twist to the individual yarns conducted through the shaft during periodic alternations in the direction of rotary motion of the shaft by the Ferrari's motor. An electrical or electro-mechanical regulating device is used in conjunction with the motor to control the periodic alternation of direction of rotation of the motor. In this manner it is possible to increase the twistalternation frequency over the mechanically driven twisting mechanism described in said patent with correspondingly increased twisting velocity and, accordingly, if desired, also increased linear yarn velocities.

Rotary heads which utilize a tubular, drilled shaft of an alternating-current motor for transitory, false twisting of a yarn that is passing through are known in the art. The combination of this invention dilfers from these known, false-twisting devices because in the latter the motor turns constantly in the same direction, whereas in our invention it periodically alternates its turning direction. A further essential distinction lies in the fact that in the known false-twist devices the motor and shaft remain in fixed position, whereas in our invention the motor and shaft are reciprocated transversely whereby the shaft is used simultaneously as a traverse-motion, yarn laying device for laying the pseudo-twisted yarn in superposed layers on the winding spool or bobbin.

The periodic alternation of the turning direction of the reversing motor may be controlled by means of electrical or electronic or electromechanical regulating devices known in the art, for example, as a time relay which always, after expiration of a certain period of time, automatically reverses the polarity of the motor. With such regulators, however, there is an after-running of the motor, following the rotation-reversing signal, of nonprecisely controllable, relatively long duration. The after-running of the motor is usually greater in one direction than in the other so that the summation of such difierences brings about a superimposition of a twist in one direction on the alternating twist. The net result is a gradually constantly increasing twist of the running yarns about each other in one direction of the yarn portions between the feed source and the twist imparter twisting the yarn ahead of the twist imparter unnecessarily and, in some cases, eventually causing yarn breakage.

In order to assure that the amount of angular turn in each direction he as uniform as possible, the angular turn or the number of turns in the one direction and then in the other direction is limited by mechanical stops. For this purpose, these stops can be designed to have a dual function--as limit switches, reversing the polarity of the motor, and simultaneously stopping mechanically the rotary movement of the motor. The arrangement of such stops, especially mechanical ones, calls for the rotating parts of the reversing motor to have as little inertia as possible, so that the forces for shifting of the turning direction or in control thereof remain slight. Small inertia is achieved to an especially high degree through the use of the Ferraris motor, Whose bell-shaped aluminum rotor is of very small mass.

In the drawing, one embodiment of the invention herein described is illustrated in detail.

Figure l of the drawing is a side elevation, partly in cross-section, of a Ferraris motor, coupled with a rotatably oscillatable twist imparter;

Figure 2 is an end elevation of the twister taken on section 22 of Figure 1;

Figure 3 is a wiring diagram for the motor circuit of the alternating-twister of Figure 1.

Referring to the drawing, the motor drive for the alternating-twist imparting member 2 is a Ferraris motor 1.

The Ferraris motor is a single-phase, eddy current type motor with a condenser circuit. It has a fixed, central core C of laminated discs 3 of iron or other magnetic field-conducting metal, constituting a magnetic reflux body, and stationary, laminated iron field magnet pairs P P and P P, (the latter not shown in Figure 1) fixed to the shell or housing of the motor 1, which field magnets together with their respective windings W constitute spaced pole pieces and form the field components of the motor. In the air gap between the field magnets P to P and the core C is positioned a cylindrical portion of the bell-shaped armature 6 of the motor. The armature 6 is made of an electrically conductive material and is preferably nonmagnetic. For purposes of this invention, the armature should be of small mass in order that large moments of inertia be avoided when the direction of rotation of the armature is reversed. Aluminum has all of these qualities and is an ideal material for the armature 6. The armature 6 is fixedly mounted at 7 on the tubular shaft 8. The shaft 5 is rotatably journalled in bearing 9 which, in turn, is axially positioned in an integral part of the motor housing 14). The bearing 9 also supports the fixed inner core C, and the outer poles P P P and P are secured to the inner wall of. the housing 10. The motor housing and associated twisting mechanism are mounted on a reciprocable support 4 which is reciprocally driven by a conventional mechanism (not shown) in a direction parallel with the axis of the winding spool or bobbin 5, which also may be a winding reel, tube, mandrel or the like.

3 The motor is powered by alternating current of, for

example, standard 60-cycle frequency. Because of the low mass of the armature 6, the reversal of direction of rotation can beachieved m fractions ofa secondv- The angular velocityof rotation-ofthe armaturerfi can be regulated by-the length ofthe cylindrical' portion thereof in the air gap. By shortening/thecylindrical..

portion or'shifting thegentire armature in a lateral di rection whereby the'cylindrical portion occupies less Olirih air gap ibetweenthe 'poles" and the core,.the angularyel locity of the armature is decreased at a given excitation of the field windings-. This feature permits adjustment? of the'number of twists of. the yarns in each direction by changing the angular velocity'ofthe-armaturexfivhile.

maintaining the samezlinear speed in ther yarnsnbeing drawn through-the shaft 8. Alternatively; it provides a manually adjustable-means to alter the frequency of twist reversal in accordancewith increases or decreases in the .linearvelocity of th e-yarnsto maintain substantially constant degrees of twist.

The axial bore 11 through the entire-length of tubular shaft 8 is' provided to conduct the yarns Ybeing twisted V therethrough and carries at one end a member 2 forconverting the rotary movement of shaft8 Qto a twisting.

The entire thread-.twistingwmechanis m may be mounted on a reciprocating member and action on the yarns.

thus serve simultaneously as a traverse-motion thread guide in winding the pseudo-twisted yarns; -threads, etc., in superposed layers on the winding spool or bobbin '5.

In order'to limit precisely the number of turns by shaft 8 in the'one direction and then in the'other, there is fixedly mounted inthe embodimentillustrated; a me the stopping mechanism -isa;follower plate 18,- which is mounted on the sleeve 19; The sleeve-19 slides-on square rod 29 in reciprocal, nonrotatable fashionc The rod 20 istsecured atits two endsinthecarrierll; which, in turn, is mounted on motor housing 10:

One embodiment of the component which-impartsathe twisting action to the running yarnsiis shownin Figure 2 This component comprises a hemispherical cap 22 cover ing the endof the axial bore 11: of shaft 8. The cap 22 hasa plurality of apertures23, througlrwhich the-=indi-;

vidual yarns run. As the cap 22rotates withthe shaft 8;

it imparts tothe yarns Y a' twisting action about each: other. Preferably, there'isone aperture for. each yarn Other twist-imparting components; such as cooperating rollers, may be used in ourinventioninstead;

filament.

of the apertured cap-22.

Figure 3 shows the wiring diagram for the alternatingtwist imparter.

is transformed by three'secondarywindings 35," 36 and 37, into separate power supplies. The heating units of the thyratrons 38- and 39 are connected *to winding'35f in a manner not drawn in detail.- 'The operating current of the Ferraris motor'l is drawn from 'winding, 36,."and the anode potential for thetwothyratrons 38-and 39*are drawn from-winding 37. A relay 41 periodically oper ates the switching-over for the opposite'rotating direc- The current-main transformer 31 is i connected to the AC. supply byway,of a switchBZ'and the fuses 33 and 33. The-power 'in'm'ain winding 34' tion of the single phase, condenser motor -1, designed according to the Ferraris principle."

Since the switching times of the 'tW0 thy1'at1'OnS.38 7 and 39 are not exactly identical, besides the balancing,

variable resistances-42 and;43,' a mechanical locking-of the motor is also recommended; 'I'hisis-composedfas represented inFigure 1, of components 13".21'.

gang switch 47 serves as an? initial'heating switch; It is open during the heating of the thyratrons and also in short operational pauses... The timing systemfdr re- J 4.. versing polarity of the motor 1 is composed of the two thyratrons with condensers and resistances in a known arrangement.

With gang switch 47 closed, which may be automatically operated, if desired, in order to prevent an inadvertent switching during the heating of the thyratrons, the current flows from the secondary coil 36 through switch 47 and the double pole, reversing switch 48 of relay 41 to the Ferraris motor 1, once directly, the next time by way of the condenser 49, which brings about an electrical advance by From the motor, the geometric sum of the two currents flows over the switch 47 back to the secondary coil 36 of transformer 31. By operation of relay 41, the direction of rotation of the motor 1 is changed, as the switch-over contact 48 of relay 41 reverses the polarities of the motor windings.

From the secondary winding 37 of transformer 31 the current is conducted over a rectifier 50 in bridge cir cuit to the filter circuit composed of coil 41- andcondensers 52 and 53. This provides asmoothed directcurrent potential.

The previously described switchingsystemperiodically switches at sequencesthe-direction of rotation; of-ithe' motor from clockwise to counterclockwise'and back again. The time periods can be changed with the' aid of the rheostats 42 and 43. t Here-the essential-feature is that the number of clo'ckwiseandcounterclockwise rotation is always of equal. angula'rmagnitude; Absolute uniformity of the angular magnitudes of the alternating, counterclockwise and clockwise directionsof- 'rot'ation is achieved according to the'invention by the described mechanical stopping mechanism.

At the closing of switch -47, a positive impulse is trans'--' mittedacross the condenser 54 and resistance 61 to the.

grid of the thyratron 39. This impulse causes-thetube to be ignited. The'anode and the grid of thyratron39 now accept the potential of the arc voltage, so that thecondensers 55 and 56- have anopportunity-to-become charged by way of resistance '57 with a potential close to the operating voltage. When the tube 38 ignitesby impulse to the grid from condenser 58 via-resistance 6%), the potential of its anode drops to the valueof the arc potential, so that the-condenser 55, before it--is'- reversed,

charged over resistances 42 and 59. At-the ignition 'ofthyratron 38, relay 41 is operated andswitches the-mo tor into the opposite direction of rotation.

This process of alternate. firing of thyratrons 38- and 39 operates relay 41 and its double pole, reversing switch 48 in timed sequence to reverse polarity of themotor 1 and thereby provide an alternating direction of rotation of the shaft 8. The 'mechanical stops assure equal degrees of angular rotation in each direction. 1

The winding of the plurality of yarns in-an' alternating direction pseudo-twist is achieved by drawing the yarns through the rotatably oscillating hollow shaft 8 and'apertures 23 of twisting component 22 onto the rotating winding spool or bobbin 5. The twist in alternatingdirections is imparted in the running yarn segment between thetwisting component 22 and the point of contact of theyarns on the yarn winding of the spool 5. The amount-of twist in each direction may be varied between one crossover of the 'yarns to several cross overs per direction of twist. The twist in each direction is secured 'againstum twisting when the twisted yarn-portions are laid on the thread body on the winding-spool or bobbin The ulti-E previously mate yarn winding consists of a plurality of superposed, wound layers of a plurality of simultaneously wound yarns with a plurality of twists about each other in alternating, opposite directions in each layer. The major advantage of this type of winding is that each of the yarns have substantially equal tensions and lengths. As the yarns subsequently are drawn off the spool or bobbin, their equiangular twists in opposite directions cancel each other-leaving a plurality of separated yarn filaments running in parallel manner at substantially equal lengths and tensions.

The invention is hereby claimed as follows:

1. In an apparatus for winding a plurality of filamentary elements with periodic alternating twists about each other in opposite directions, a reversible, eddy current electric motor having an aluminum armature and a hollow shaft driven by the armature of said motor, said hollow shaft adapted to conduct a plurality of filamentary elements therethrough, means associated with said hollow shaft and rotatable therewith for imparting a twist to the filamentary elements about each other when said means is rotated, control means for reversing the direction of rotation of said motor at substantially constant periodic intervals, and a mechanical stopping mechanism operable on said shaft for stopping the angular rotation of said shaft in each direction to provide equal degrees of angular rotation of said shaft by said armature in each direction of rotation.

2. In an apparatus for winding a plurality of filamentary elements with periodic alternating twists about each other in opposite directions, a single phase, reversible, eddy current electric motor having a fixed core and fixed poles with an electrically conductive armature having a cylindrical segment in the air gap between said core and poles, a hollow drive shaft connected to said armature, said hollow shaft adapted to conduct a plurality of filamentary elements therethrough, means associated with said hollow shaft and rotatable therewith for imparting a twist to the filamentary elements about each other when said means is rotated, control means for reversing the direction of rotation of said motor at substantially constant periodic intervals, and a mechanical stopping mechanism operable on said shaft for stopping the angular rotation of said shaft in each direction to Provide equal degrees of angular rotation of said shaft by said armature in each direction of rotation.

3. In an apparatus for winding a plurality of filamentary elements with periodic alternating twists about each other in opposite directions, a reversible electric motor having a hollow shaft driven by the armature of said motor, said hollow shaft adapted to conduct a plurality of filamentary elements therethrough, means associated with said hollow shaft and rotatable therewith for imparting a twist to the filamentary elements about each other when said means is rotated, control means for reversing the direction of rotation of said motor at substantially constant periodic intervals, and a mechanical stopping mechanism operable on said drive shaft for stopping the angular rotation of Said shaft in each direction to provide equal degrees of angular rotation in each direction of rotation of said shaft by said armature.

4. In an apparatus for winding a plurality of filamentary elements with periodic alternating twists about each other in opposite directions, a reversible electric motor having a hollow shaft driven by the armature of said motor, said hollow shaft adapted to conduct a plurality of filamentary elements therethrough, means associated with said hollow shaft and rotatable therewith for imparting a twist to the filamentary elements about each other when said means is rotated, control means for reversing the direction of rotation of said motor at substantially constant periodic intervals, and mechanical stopping mechanism including a spirally grooved element attached to said drive shaft, two spaced stopping elements in the spiral groove, and a follower slidably and nonrotatably mounted on a slide rod, said follower extending into said spiral groove and adapted to contact said stopping elements to thereby mechanically stop rotation of said shaft.

References Cited in the file of this patent UNITED STATES PATENTS 2,751,747 Burleson June 26, 1956 2,837,889 Comer June 10, 1958 2,863,277 Boillat et a1. Dec. 9, 1958 

